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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
331

Caracterização temporal e espacial da temperatura do ar e da evapotranspiração de referência na Bolívia / Caracterización temporal y espacial de la temperatura del aire y la evapotranspiración de referencia en Bolivia

Choque Conde, Esteban [UNESP] 14 June 2017 (has links)
Submitted by ESTEBAN CHOQUE CONDE null (condesteban@fca.unesp.br) on 2017-06-30T15:14:51Z No. of bitstreams: 1 Esteban-Choque-Conde.pdf: 12634736 bytes, checksum: d8da7485161968cf5d5723a8b589c057 (MD5) / Rejected by Luiz Galeffi (luizgaleffi@gmail.com), reason: Solicitamos que realize uma nova submissão seguindo as orientações abaixo: No campo “Versão a ser disponibilizada online imediatamente” foi informado que seria disponibilizado o texto completo porém no campo “Data para a disponibilização do texto completo” foi informado que o texto completo deverá ser disponibilizado apenas 6 meses após a defesa. Caso opte pela disponibilização do texto completo apenas 6 meses após a defesa selecione no campo “Versão a ser disponibilizada online imediatamente” a opção “Texto parcial”. Esta opção é utilizada caso você tenha planos de publicar seu trabalho em periódicos científicos ou em formato de livro, por exemplo e fará com que apenas as páginas pré-textuais, introdução, considerações e referências sejam disponibilizadas. Se optar por disponibilizar o texto completo de seu trabalho imediatamente selecione no campo “Data para a disponibilização do texto completo” a opção “Não se aplica (texto completo)”. Isso fará com que seu trabalho seja disponibilizado na íntegra no Repositório Institucional UNESP. Por favor, corrija esta informação realizando uma nova submissão. Agradecemos a compreensão. on 2017-06-30T16:25:27Z (GMT) / Submitted by ESTEBAN CHOQUE CONDE null (condesteban@fca.unesp.br) on 2017-07-01T13:02:11Z No. of bitstreams: 1 Esteban-Choque-Conde.pdf: 12634736 bytes, checksum: d8da7485161968cf5d5723a8b589c057 (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-07-04T17:06:41Z (GMT) No. of bitstreams: 1 choqueconde_e_dr_bot.pdf: 12634736 bytes, checksum: d8da7485161968cf5d5723a8b589c057 (MD5) / Made available in DSpace on 2017-07-04T17:06:41Z (GMT). No. of bitstreams: 1 choqueconde_e_dr_bot.pdf: 12634736 bytes, checksum: d8da7485161968cf5d5723a8b589c057 (MD5) Previous issue date: 2017-06-14 / Item merged in doublecheck by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-07-18T17:58:20Z Item was identical to item(s): 151818, 151941 at handle(s): http://hdl.handle.net/11449/151034, http://hdl.handle.net/11449/151112 / Asociación Universitaria Iberoamericana de Postgrado (AIUP) / O presente pesquisa teve por objetivo estudar a temperatura do ar e a evapotranspiração de referência (ETo) nas diferentes zonas agroecológicas da Bolívia (Lhanos, Vales e Andina) por meio de modelos estatísticos e geoestatísticos, com base de dados de temperatura do ar de 235 estações meteorológicas da Bolívia e 41 de países vizinhos. O estudo é apresentado em dois capítulos: O primeiro descreve a caracterização dos valores de temperatura média (Tmed) máxima (Tmax) e mínima (Tmin) do ar, mediante três distribuições espaciais: Departamentos, bacias hidrográficas e zonas agroecológicas, sendo esta última a melhor alternativa de análise. Uma análise de regressão linear permitiu a obtenção das equações de estimativa Tmed, Tmax e Tmin em função da altitude, com elevados coeficientes de determinação (R2). Os desvios resultantes das comparações entre os valores estimados das equações sazonais e mensais em relação à média anual sugerem, na maioria das altitudes, o uso das equações sazonais ou mensais, particularmente para Tmed e Tmin. Foram apresentados as variações espaciais da Tmed, Tmax e Tmin por meio de mapas isotérmicas. Os mapas comprovam a forte influência da altitude sobre valores de Tmed, Tmax e Tmin, colocando isotermas de valores mais altos na zona dos Lhanos (zonas baixas) e, de valores mais baixos na zona Andina (zonas altas). O segundo capítulo, descreve a caracterização da ETo nas três zonas agroecológicas da Bolívia, utilizando a temperatura como variável de entrada: McGuinness – Bordne, Hargreaves – Samani e Thornthwaite. Os três métodos, mostram que os aumentos da altitude e latitude determinam uma diminuição da ETo, no sentido da zona dos Lhanos para a zona Andina. O análise de regressão linear com os três métodos permitiu a obtenção das equações anuais de estimativas para a ETo em função da altitude, com melhor resultado para o modelo de McGuinness – Bordne, cujo R2 foi o mais elevado. Os desvios resultantes das comparações entre equações dos valores de ETo sazonais e mensais em relação à anual sugerem, na maioria das altitudes, o uso das equações sazonais ou mensais. As variações espaciais da ETo apresentadas por meio de mapas de isolinhas, corroboram a forte influência da altitude sobre valores de ETo, colocando isolinhas de valores mais altos na zona dos Lhanos, e de valores mais baixos nas zona Andina. / The objective of this research was to study air temperature and reference evapotranspiration (ETo) in the different agroecological zones of Bolivia (Plains, Valleys and Andean) using statistical and geostatistical models, with air temperature database of 235 meteorological stations in Bolivia and 41 of neighboring countries was used. The study is presented in two chapters: The first describes the characterization of the values of the medium (Tmed) maximum (Tmax) and minimum (Tmin) air temperature, through three spatial distributions: Departments, hydrographic basins and agroecological zones. Being the latter the best alternative of analysis. Linear regression analysis allowed to obtain the estimation equations for Tmed, Tmax and Tmin in function of altitude, with high determination coefficients (R2). The deviations resulting from comparisons between the seasonal and monthly equations estimated values in relation to the annual average suggest, in most altitudes, seasonal or monthly equations use, mainly for Tmed and Tmin. Were presented the spatial variations Tmed, Tmax and Tmin through isothermal maps. The maps show the strong influence of altitude on temperature values, placing higher isotherms in the Plains zone (lowlands) and lower in the Andean zone (highlands). The second chapter describes the characterization of ETo in the three agroecological zones of Bolivia, using temperature as the input variable: McGuinness - Bordne, Hargreaves - Samani and Thornthwaite. All three methods show that altitude and latitude increases determine an ETo decrease, in the direction of the Plains zone to the Andean zone. The three methods linear regression analysis helped obtaining the ETo annual estimation equations in function of altitude, with McGuinness - Bordne model showing the best result, as its R2 was the highest. The deviations resulting from comparisons between equations of seasonal and monthly ETo values in relation to the annual values suggest, at most altitudes, seasonal or monthly equations use. The ETo spatial variations are presented through isoline maps, corroborate the strong influence of altitude in ETo values by placing isolines of higher values in the Plains zone, and of lower values in the Andean zone. / La presente investigación tuvo por objetivo estudiar la temperatura del aire y la evapotranspiración de referencia (ETo) en las diferentes zonas agroecológicas de Bolivia (Llanos, Valles y Andina) a través de modelos estadísticos y geoestadísticos, con base de datos de temperaturas del aire de 235 estaciones meteorológicas de Bolivia y 41 de países vecinos. El estudio es presentado en dos capítulos: El primero describe la caracterización de valores de la temperatura media (Tmed) máxima (Tmax) y mínima (Tmin) del aire, mediante tres distribuciones espaciales: Departamentos, cuencas hidrográficas y zonas agroecológicas. Siendo esta última la mejor alternativa de análisis. Un análisis de regresión lineal logró obtener las ecuaciones anuales que estiman la Tmed, Tmax e Tmin en función de la altitud, con elevados coeficientes de determinación (R2). Las desviaciones resultantes de comparaciones entre las ecuaciones estacionales y mensuales en relación a la media anual sugieren, en la mayoría de las altitudes, el uso de ecuaciones estacionales o mensuales, particularmente para Tmed e Tmin. Fueron presentadas las variaciones espaciales de Tmed, Tmax e Tmin por medio de mapas isotérmicas, los mapas evidencian la fuerte influencia de la altitud sobre valores de Tmed, Tmax e Tmin, marcando isotermas de valores más altos en la zona de los Llanos (zonas bajas) y, de valores más bajos en la zona Andina (zonas altas). El segundo capítulo describe la caracterización de ETo en tres zonas agroecológicas de Bolivia, utilizando la temperatura del aire como variable de entrada: McGuinness - Bordne, Hargreaves - Samani y Thornthwaite. Los tres métodos demuestran que los aumentos de altitud y latitud determinan una disminución de ETo, en el sentido de la zona de los Llanos para la zona Andina. El análisis de regresión lineal con los tres métodos, facilitó la obtención de ecuaciones de ETo en función de la altitud, con mejor resultado para el método McGuinness - Bordne con R2 más alto. Las desviaciones resultantes de las comparaciones entre las ecuaciones de ETo estacionales y mensuales en relación a la anual sugieren, en la mayoría de las altitudes, el uso de ecuaciones estacionales o mensuales. Las variaciones espaciales de ETo presentados por medio de mapas de isolineas, corroboran la fuerte influencia de la altitud, colocando isolineas de valores más altos en la zona de los Llanos y, de valores más bajos en la zona Andina (zonas altas).
332

Podrobné zaměření polohopisu a výškopisu v části povodí Ostřice jako podklad ke sledování dlouhodobých změn krajiny. / Detailed surveying of planimetry and altitude points in the part of the area of the river Ostřice as control points in order to watch long time changes of the landscape.

HOJDEKR, Michal January 2009 (has links)
The subject of my diploma project has been detailed surveying of planimetry and altitude points in the part of the area of the river Ostřice as control points in order to watch long time changes of the landscape. Mapping work carried out in the surroundings of the village land Hodňov in the cadastral territory of Horni Plana 5-2 in the approximate area of 27 hectare. The aim of this work was the creation of planimetric and hypsographic plan at a scale of 1:500, which was based on field reconnaissance and the current point field, the proposal stabilization and surveying detailed points, a detailed surveying situation, computational work and graphic processing. The alignment of interest locations were used tacheometrical method. Height detailed and auxiliary points were determined trigonometric and situation were determined polar. For measurement purposes was used a total station Leica TCR 407 power. The coordinates of all points are identified in the system S-JTSK and height are identified in the system BPV.
333

Posouzení biodiverzity dřevin v závislosti na nadmořské výšce v okolí vybraných naučných stezek NP a CHKO Šumava / Review of the biodiversity of tree species commensurate with the altitudes in the vicinity of chosen nature trails of National Parc and protected landscape area Šumava

BATOVCOVÁ, Martina January 2009 (has links)
I studied the biodiversity of tree species along the nature trail: Kubova Huť (1003 meters above sea level) {--} top of the national natural reservation Boubínský prales (1363 m above sea level), in the different altitudes. I carried out the measuring by the transect method. I divided all the route into 8 imaginary line-levels which were distant about 50 m above sea level one from each other. On each level 6 transects were delimited at right angle to the direction of the trail: 3 on the right side and 3 on the left side of the trail, always with the distance of 10 m between each other. I delimited the square areas of 30 square meters as transects. In each transect I measured identified the kinds of given tree species. I also counted the regeneration of young seedlings in 1 m-neighbourhood of each tree. I counted also rotting wood and regeneration of young seedlings in its neighbourhood. I also took down the number of snags in this area and number of regeneration around these individuals.
334

Funkční vlastnosti vysokohorských rostlin východního Ladaku (SZ Himaláje) / Functional traits of high-altitude plants in Eastern Ladakh (NW Himalayas)

CHLUMSKÁ, Zuzana January 2011 (has links)
Functional traits of 217 high altitude plants were studied in Eastern Ladakh (NW Himalayas, India). Changes in functional traits along altitudinal and moisture gradient were analysed. Plants were classified into 9 different habitats according to their frequency of occurence.
335

Eficiência do polímero GRIP® aplicado em pré colheita na qualidade de semente de soja / Efficiency of GRIP® Polymer Applied in Pre- Harvest in the Soybean Seed Quality.

Coldebella, Jeferson Santo 29 April 2016 (has links)
Submitted by Gabriela Lopes (gmachadolopesufpel@gmail.com) on 2018-07-16T20:14:36Z No. of bitstreams: 1 Versao final da monografia Jeferson versão definitiva 2 (1)-1.pdf: 159729 bytes, checksum: 4d19f28227e500b46e5d8ad6ee00ffb8 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-07-17T21:27:10Z (GMT) No. of bitstreams: 1 Versao final da monografia Jeferson versão definitiva 2 (1)-1.pdf: 159729 bytes, checksum: 4d19f28227e500b46e5d8ad6ee00ffb8 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-07-17T21:29:36Z (GMT) No. of bitstreams: 1 Versao final da monografia Jeferson versão definitiva 2 (1)-1.pdf: 159729 bytes, checksum: 4d19f28227e500b46e5d8ad6ee00ffb8 (MD5) / Made available in DSpace on 2018-07-17T21:29:44Z (GMT). No. of bitstreams: 1 Versao final da monografia Jeferson versão definitiva 2 (1)-1.pdf: 159729 bytes, checksum: 4d19f28227e500b46e5d8ad6ee00ffb8 (MD5) Previous issue date: 2016-04-29 / Em busca de tecnologias inovadoras que tragam resultados na manutenção da qualidade fisiológica de campo de sementes de soja, instalados em regiões não propícias para produção de sementes, a principal necessidade da empresa I. Riedi é de produzir suas próprias sementes, para dessa forma, facilitar a logística de comercialização. O presente trabalho teve como objetivo avaliar o desempenho do produto a base de látex e silicone de nome comercial GRIP®, na diminuição dos efeitos danosos da chuva na fase de pré-colheita de campos de produção de sementes de soja. Os experimentos foram conduzidos em duas regiões distintas em altitude dentro do Estado do Paraná na cidade de Clevelândia à 925m de altitude e em Cascavel a 550m de altitude, localizadas no oeste e sudoeste do Estado, respectivamente. Testaram-se três tratamentos: sementes colhidas antes da chuva, após a chuva com aplicação de GRIP® e após a chuva sem aplicação de GRIP®. Os dois experimentos foram conduzidos utilizando a cultivar SYN1059 RR, blocos ao acaso com 7 repetições. Todos os dados obtidos na analise foram submetidas a análise de variância, foi efetuada a comparação de médias, através do Teste de Tukey ao nível de significância de 5%. O programa Sisvar® foi utilizado para execução da analise e obtenção dos resultados. No momento em que o campo de sementes encontrava-se na fase de pré-colheita e precedendo uma chuva em 24horas, efetuou-se aplicação do polímero nas parcelas. Imediatamente após a chuva as sementes de soja da parcela foram colhidas no momento em que atingiram o ponto de colheita (14%) e as amostras foram encaminhadas ao laboratório para determinar germinação e vigor no tempo zero (imediatamente após a colheita) e 3 meses de armazenamento. Conclui-se que para região de baixa altitude o produto GRIP® não preserva a qualidade fisiológica das sementes de soja produzidas após chuva. Na região de alta altitude o produto mostrou um desempenho superior para vigor após as sementes de soja terem recebido chuva na pré-colheita. / In search of innovative technologies that bring results in maintaining the physiological quality of soybean field, installed in areas not conducive to seed production, the primary need of I. Riedi company is to produce their own seeds, to thus facilitate the marketing logistics. This study aimed to evaluate the performance of the product based on latex and silicone trade name Grip®, in reducing the damaging effects of rain in the pre-harvest soybean seed production fields phase. The experiments were conducted in two different regions in altitude within the state of Paraná in the city of Clevelândia at 925m altitude and Cascavel to 550m above sea level, located in the west and southwest of the state, respectively. Were tested three treatments: seeds harvested before the rain, rain after application Grip® with and without rain after application Grip®. Both experiments were conducted using the cultivar SYN1059 RR, a completely randomized with six replications, randomized blocks. The statistical program used was Minitab with Tukey at 5% significance. At the moment the seed was in the field pre-harvest stage and preceding a rain in 24 hours, was executed application on portions of the polymer. After the rain seeds were harvested and compared in laboratory results (germination and vigor) at zero time (immediately after harvest) and 3 months of storage. It is concluded that for low-altitude region Grip® the product does not preserve the physiological quality of soybean seeds produced after rain. In the high-altitude region the product showed superior performance to force after the soybeans have received rain in the pre-harvest.
336

Campos de altitude do Parque Estadual da Serra do Papagaio, Minas Gerais, Brasil: composição florística, fitogeografia e estrutura da vegetação

Mendonça, Júlia Gaio Furtado de 19 June 2017 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-09-05T15:53:23Z No. of bitstreams: 1 juliagaiofurtadodemendonca.pdf: 4297836 bytes, checksum: 611aa9bbd15f00fc16fe7b8ca2925468 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-09-06T11:32:11Z (GMT) No. of bitstreams: 1 juliagaiofurtadodemendonca.pdf: 4297836 bytes, checksum: 611aa9bbd15f00fc16fe7b8ca2925468 (MD5) / Made available in DSpace on 2017-09-06T11:32:11Z (GMT). No. of bitstreams: 1 juliagaiofurtadodemendonca.pdf: 4297836 bytes, checksum: 611aa9bbd15f00fc16fe7b8ca2925468 (MD5) Previous issue date: 2017-06-19 / O Parque Estadual da Serra do Papagaio (PESP), situado na porção Meridional da Serra da Mantiqueira, sul de Minas Gerais, representa uma grande extensão de formações vegetacionais altimontanas com altitudes que alcançam 2.350 m. O objetivo deste trabalho foi conhecer a composição florística dos campos de altitude do PESP, suas relações fitogeográficas com outras áreas campestres das regiões Sul e Sudeste do Brasil e analisar a estrutura da vegetação ao longo de um gradiente altitudinal. Expedições mensais de campo foram realizadas entre maio de 2015 e outubro de 2016 para coleta de material botânico e realização dos inventários fitossociológicos. Para avaliar a estrutura da vegetação foi utilizado o método de interceptação em linha, com alocação de nove áreas abrangendo três faixas altitudinais entre 1.650 m e 2.050 m. Para analisar as relações fitogeográficas foram selecionadas 14 localidades do Sul e Sudeste do país. Foram realizadas análises de similaridade quantitativas e qualitativas além do cálculo da diversidade para cada faixa altitudinal para avaliar a formação de grupos relacionados à altitude. O primeiro capítulo traz a composição florística dos campos de altitude do PESP, onde foram encontradas 276 espécies, 159 gêneros e 48 famílias de angiospermas, sendo Asteraceae a família mais rica (58 spp.) e Baccharis o gênero mais representativo (12 spp.). Foram encontradas onze espécies sob algum grau de ameaça e duas espécies endêmicas do PESP. As análises fitogeográficas mostraram uma grande dissimilaridade florística entre as 14 localidades analisadas, indicando que as formações campestres são singulares e demandam atenção especial para a conservação. O segundo capítulo apresenta a distribuição das espécies ao longo de um gradiente altitudinal. Foram encontradas 96 espécies nas linhas amostradas, sendo Poaceae (64,3%), Melastomataceae (11,3%) e Asteraceae (8,7%) as famílias com maiores valores de cobertura. A diversidade de Shannon (H’) para cada altitude apontou um padrão similar na distribuição espacial das espécies, enquanto as análises de similaridade demonstraram um forte agrupamento das áreas localizadas em faixas altitudinais comuns, elucidando a importância da conservação dos campos de altitude para a manutenção da biodiversidade da flora altomontana. / The Parque Estadual da Serra do Papagaio (PESP) is located in the southern portion of Serra da Mantiqueira, south of Minas Gerais and represents a large expanse of altitudinal vegetation formations with altitudes that reach 2.350 m. The aim of this work was to carry out the floristic survey of the PESP altitude fields (campos de altitude), their phytogeographic relationships with other rural areas of Southern and Southeastern regions of Brazil, and to analyze the vegetation structure along an altitudinal gradient. Monthly expeditions were carried out between May 2015 and October 2016 for the collection of botanical material and the realization of phytosociological inventories. The line intercept method was used to evaluate the vegetation structure. Were inventoried nine areas covering three altitudinal ranges between 1.650 m and 2.050 m. In order to analyze the phytogeographic relations, were selected 14 localities of Brazil South and Southeast. Quantitative and qualitative similarities analyzes were carried out. In addition, the diversity index (H') were calculated for each altitudinal range in order to evaluate the formation of groups related to altitude. The first chapter presents the floristic composition of the PESP altitude fields, where 276 species, 159 genera and 48 families of angiosperms were found, with Asteraceae being the richest family (58 spp.) and Baccharis the most representative genus (12 spp.). Eleven species are in some threatness category and two species were considered endemic to the PESP. The phytogeographic analyzes showed a great floristic dissimilarity between the 14 localities analyzed, indicating that the formations are unique and require special attention for conservation. The second chapter presents the distribution of the species along an altitudinal gradient. 96 species were found in the sampled lines, with Poaceae (64.3%), Melastomataceae (11.3%) and Asteraceae (8.7%) being the families with the highest coverage values. The diversity of Shannon (H') for each altitude showed a similar pattern in the spatial distribution of species, while the similarity analyzes demonstrated a strong grouping of the areas located in common altitudinal bands, elucidating the importance of the conservation of altitude fields for the maintenance of the biodiversity of the high altitude flora.
337

Hypoxia-inducible factor prolyl 4-hydroxylase-2 in Tibetan high-altitude adaptation, extramedullary erythropoiesis and skeletal muscle ischemia

Myllymäki, M. (Mikko) 07 June 2016 (has links)
Abstract Adequate oxygen supply is necessary for aerobic cell survival. Cellular oxygen deprivation, also known as hypoxia, leads to various responses that aim to increase cellular oxygen delivery and reduce oxygen consumption. Oxygen homeostasis is mainly regulated by the hypoxia-inducible factor (HIF), which regulates the expression of over 300 genes in response to hypoxia. The stability of HIF is regulated by the HIF prolyl 4-hydroxylases (HIF-P4Hs), enzymes that catalyze the hydroxylation of proline residues in HIFα subunits and target them towards proteasomal degradation. HIF-P4Hs require oxygen as a cosubstrate for the reaction, allowing for hypoxic HIF stabilization and target gene induction at low oxygen concentrations. In this study we investigated the role of HIF-P4H-2 in the regulation of red blood cell production, erythropoiesis. We showed that Tibetans living at high altitude have genetically adapted to their hypoxic environment via mutations in the gene encoding for HIF-P4H-2. The Tibetan HIF-P4H-2 D4E,C127S variant showed enhanced hydroxylation of HIFα at low oxygen concentrations, resulting in reduced HIFα protein stabilization under hypoxia. In other studies we used a genetically modified HIF-P4H-2 hypomorphic mouse line which expresses a reduced amount of wild-type Hif-p4h-2 mRNA in tissues. We showed that these mice develop mild age-dependent erythrocytosis due to splenic extramedullary erythropoiesis, which is independent of serum erythropoietin concentration. In addition, these mice were protected against inflammation-induced anemia, a condition commonly seen in patients with inflammatory diseases. The HIF-P4H-2 hypomorphic mice also had altered basal metabolism in their skeletal muscles, which, together with an increase in mean capillary area, reduced their infarct size after skeletal muscle ischemia-reperfusion injury. These studies suggest that pharmacological HIF-P4H-2 inhibition may provide a novel treatment for EPO-resistant anemias and peripheral artery disease. / Tiivistelmä Riittävä hapensaanti on välttämätöntä aerobisten solujen selviytymiselle. Solun alentunut hapen määrä, toiselta nimeltään hypoksia, johtaa useisiin vasteisiin joiden tarkoituksena on turvata solun hapensaanti ja vähentää hapenkulutusta. Happitasapainoa säätelee hypoksiassa indusoituva tekijä (HIF), joka aktivoi yli 300 geenin luentaa hypoksisissa oloissa. HIFα:n määrää soluissa säätelevät HIF prolyyli-4-hydroksylaasientsyymit (HIF-P4H:t), jotka hydroksyloivat proliini-aminohappotähteitä HIFα-alayksiköissä ja ohjaavat ne proteasomaaliseen hajotukseen. HIF-P4H:t tarvitsevat reaktiossa happea mahdollistaen HIF:n stabilisaation ja kohdegeenien lisääntyneen luennan matalassa hapen osapaineessa. Tässä tutkimuksessa selvitimme HIF-P4H-2-entsyymin roolia punasolujen muodostuksen eli erytropoieesin säätelyssä. Osoitimme, että korkealla vuoristossa asuvat tiibetiläiset ovat geneettisesti sopeutuneet hypoksiseen elinympäristöönsä johtuen HIF-P4H-2-entsyymiä tuottavan geenin mutaatiosta. Tiibetiläisiltä löytynyt HIF-P4H-2D4E,C127S variantti hydroksyloi tehokkaammin HIFα-alayksiköitä matalassa hapen osapaineessa johtaen vähäisempään HIFα-alayksiköiden stabiloitumiseen hypoksiassa. Muissa tutkimuksissamme käytimme geneettisesti muunneltua HIF-P4H-2-hiirikantaa, joka tuottaa alentunutta määrää villityypin Hif-p4h-2 lähetti-RNA:ta kudoksissaan. Näille hiirille kehittyi ikäriippuvaisesti lievä punasoluylimäärä eli erytrosytoosi johtuen pernan kiihtyneestä punasolutuotannosta riippumatta seerumin erytropoietiinikonsentraatiosta. Lisäksi nämä hiiret olivat suojassa tulehduksen aiheuttamalta anemialta, joka on yleinen ilmiö tulehduksellisista sairauksista kärsivillä potilailla. HIF-P4H-2-muuntogeenisten hiirten lihasten energia-aineenvaihdunta oli muuttunut siten, että se yhdessä suurentuneen keskimääräisen kapillaaripinta-alan kanssa pienensi vaurioituneen kudoksen pinta-alaa alaraajaiskemia-altistuksen jälkeen. Nämä tutkimukset osoittavat, että lääkkeellinen HIF-P4H-2-entsyymin estäminen on mahdollinen uusi hoitomuoto erytropoietiinille resistenteissä anemioissa sekä alaraajojen valtimoahtaumataudissa.
338

Improving the System Performance of High Altitude Platforms Serving Suburban Areas / Improving the System Performance of High Altitude Platforms Serving Suburban Areas

Hasan, Md. Al-Mahadi, Islam, Mainul January 2012 (has links)
High Altitude Platforms (HAP) has been evolving to make a new history in wireless communications infrastructure. A number of applications and services have been proposed for HAP based communications which advance HAP over terrestrial and satellite infrastructure for future communications. Providing high speed multimedia mobile communications through HAPs to the users of Third Generation (3G) holds strong position using one of the proposed band, 2GHz. In this study we investigated how to improve the performance of 3G serving from HAP over a territory having suburban characteristics. Two proposed channel models, free space loss and shadowing loss, has been used to analyze the performance of HAP systems at 2GHz frequency band for suburban regions. Three different parameters namely antenna bore point, HAP antenna roll off factor and user antenna roll off factor have proposed to improve the performance of HAP systems while considering suburban regions. A scenario has introduced consisting of an ideal suburban and rural region to serve 3G services while emphasizing on suburban region. The number of HAPs required to serve the defined suburban region is restricted to at least three due to elevation dependent losses in the scenario. The three proposed parameters have been used to improve the performance of 3G services over the selected suburban region. Application of the parameters over suburban region gives different performances which can be categorized in different ways. Some of the parameters are more elastic than others for a certain coverage area. We conclude with adaptive application of the parameters for 3G services over suburban area to have improved performance of HAP. / +46720459586
339

Effect of environmental, developmental and genetic factors on flavonoid and carotenoid profile of Vaccinium berries

Zoratti, L. (Laura) 28 September 2015 (has links)
Abstract Vaccinium berries contain high yields of antioxidant compounds, such as flavonoids and carotenoids, which are recognized to benefit human health. Therefore, commercial interest in cultivated and wild Vaccinium berries is increasing globally. Flavonoids and carotenoids are important secondary metabolites, the biosynthesis of which is regulated by interaction of the genetic background of the plant and the surrounding environment. In fruits the production of secondary metabolites has also a tight linkage with developmental processes. The present thesis is focused on developmental and environmental factors affecting the biosynthesis of carotenoids and flavonoids in berries of the genus Vaccinium. In bilberry altogether eight carotenoids were detected, with lutein and β-carotene being the most abundant compounds, accompanied by minor amounts of xanthophylls, such as antheraxanthin, neoxanthin, violaxanthin and zeaxanthin. During ripening the accumulation of carotenoids decreased. Simultaneously the expression of a carotenoid cleavage dioxygenase (VmCCD1) gene increased, indicating degradation of carotenoids during the fruit development. Simultaneously, flavonols and anthocyanins accumulated during the last stages of berry ripening. Environmental factors had a marked effect on the anthocyanin profile of ripe bilberries. Especially lower temperatures affected more on the accumulation of the delphinidin-based anthocyanidins than on the cyanidin-based ones. However, the spectral light composition also played a role, as an increased proportion in blue wavelengths increased the delphinidin-based anthocyanins at ripe stage. The effect of light quality on other phenolic compounds and carotenoid accumulation was less pronounced. The present results can be applied to cultivation of Vaccinium species in order to produce berries with high nutritional value. / Tiivistelmä Vaccinium-suvun marjat sisältävät runsaasti antioksidatiivisiä yhdisteitä, kuten flavonoideja ja karotenoideja, joilla on viimeaikaisissa tutkimuksissa havaittu lukuisia terveysvaikutuksia. Tämän johdosta kiinnostus sekä viljeltyjä mustikoita että metsämustikoita kohtaan on kasvanut maailmanlaajuisesti. Flavonoidit ja karotenoidit ovat kasvien tuottamia sekundäärimetabolian yhdisteitä, joiden biosynteesin säätelyyn vaikuttavat sekä kasvin geneettinen tausta että ympäristötekijät. Hedelmissä ja marjoissa sekundääriyhdisteiden tuoton säätelyyn vaikuttaa huomattavasti myös kehityksellisten vaiheiden eteneminen. Tässä väitöskirjatyössä selvitettiin marjan kehitykseen liittyvien tekijöiden sekä ympäristötekijöiden vaikutusta flavonoidien ja karotenoidien biosynteesiin sekä viljelyillä mustikoilla että metsämustikoilla. Metsämustikoista tunnistettiin kahdeksan erilaista karotenoidi-yhdistettä, joista luteiini ja β-karoteeni esiintyivät yleisimpinä ksantofyllin, antheraksantiinin, neoksantiinin, violaksantiinin ja zeaksantiinin ohella. Karotenoidien pitoisuudet olivat suurimmillaan marjankehityksen alkuvaiheessa ja laskivat kypsyvissä marjoissa. Vastaavasti karotenoideja pilkkovan VmCCD1 entsyymigeenin ilmeneminen lisääntyi kohosi marjan kypysymisen loppuvaiheessa. Antosyaanien ja myrisetiini-pohjaisten flavonolien pitoisuudet sen sijaan kohosivat kypsymisen aikana. Tässä tutkimuksessa ympäristötekijöillä osoitettiin olevan suuri vaikutus antosyaanien laadulliseen kertymiseen, sillä delfinidiini-tyypin antosyaanien pitoisuudet muuttuivat enemmän ympäristötekijöiden vaikutuksesta verrattuna syanidiini-tyypin antosyaaneihin. Alhaisempi lämpötila yhdessä spesifisten valo-olosuhteiden kanssa lisäsi eniten delfinidiini-tyypin antosyaanien tuottoa. Myös valon laadulla voitiin osoittaa olevan vaikutusta antosyaanien biosynteesiin. Sininen valo lisäsi erityisesti delfinidiini-tyypin antosyaanien tuottoa kypsissä marjoissa. Flavonolien ja karotenoidien tuottoon valon laadun vaikutus oli sen sijaan vähäisempää. Väitöskirjatyön tuloksia voidaan hyödyntää marjojen viljelyssä haluttaessa vaikuttaa marjojen ravitsemukselliseen koostumukseen.
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Montane Wetlands of the South African Great Escarpment : plant communities and environmental drivers

Janks, Matthew Richard January 2015 (has links)
Wetlands provide a number of valuable functions to both the surrounding environment and society. The anaerobic conditions created by flooding in wetlands provide a habitat that supports unique assemblages of plant life. High altitude wetlands are amongst the most species-rich in South Africa. They house a number of rare species and play a vital role in the supply of water to lower lying areas. These are some of the reasons that mountain wetlands are of high conservation value. A phytosociological study was undertaken on the high altitude wetlands of the Great Escarpment with the aim of classifying the plant communities and identifying the environmental drivers of plant community patterns within these ecosystems. Data collection was focused in the Eastern Cape and was supplemented with data from existing studies to gain a more complete understanding of the wetlands of the Great Escarpment of South Africa. Using the Braun-Blanquet approach, Hierarchical Cluster Analysis and Indicator Species Analysis; five broad wetland groups were identified, comprised of 33 individual plant communities and 81 indicator species. Multivariate analysis, including Canonical Correspondence Analysis revealed that the effects of altitude, such as temperature and rainfall, are the most significant large-scale drivers of vegetation patterns. Smaller scale drivers include wetness and soil nutrients including nitrogen, phosphorus, electrical conductivity, sodium, and organic content. The identification of indicator species served to reveal potentially important wetland species across different areas of the Great Escarpment. The effects of altitude on plant community patterns highlights the susceptibility of the high altitude specific communities to upward temperature zone shifts resulting from global warming. Other threats include livestock trampling, water extraction, and land use change for agricultural purposes. The relative absence of alien species in these wetlands gives an indication of their pristine condition and therefore their importance as a reference from which they may be monitored. A large proportion of the wetlands studied here occur outside protected areas, and given the rate of wetland loss in South Africa, it is important that continued effective land management is practiced to ensure that these ecosystems are conserved in the future .

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